arch/s390/Kconfig

   1 #
   2 # For a description of the syntax of this configuration file,
   3 # see Documentation/kbuild/kconfig-language.txt.
   4 #
   5
   6 config SCHED_MC
   7         def_bool y
   8         depends on SMP
   9
  10 config MMU
  11         def_bool y
  12
  13 config ZONE_DMA
  14         def_bool y
  15         depends on 64BIT
  16
  17 config LOCKDEP_SUPPORT
  18         def_bool y
  19
  20 config STACKTRACE_SUPPORT
  21         def_bool y
  22
  23 config HAVE_LATENCYTOP_SUPPORT
  24         def_bool y
  25
  26 config RWSEM_GENERIC_SPINLOCK
  27         bool
  28
  29 config RWSEM_XCHGADD_ALGORITHM
  30         def_bool y
  31
  32 config ARCH_HAS_ILOG2_U32
  33         bool
  34         default n
  35
  36 config ARCH_HAS_ILOG2_U64
  37         bool
  38         default n
  39
  40 config GENERIC_HWEIGHT
  41         def_bool y
  42
  43 config GENERIC_TIME
  44         def_bool y
  45
  46 config GENERIC_CLOCKEVENTS
  47         def_bool y
  48
  49 config GENERIC_BUG
  50         bool
  51         depends on BUG
  52         default y
  53
  54 config NO_IOMEM
  55         def_bool y
  56
  57 config NO_DMA
  58         def_bool y
  59
  60 config GENERIC_LOCKBREAK
  61         bool
  62         default y
  63         depends on SMP && PREEMPT
  64
  65 config PGSTE
  66         bool
  67         default y if KVM
  68
  69 mainmenu "Linux Kernel Configuration"
  70
  71 config S390
  72         def_bool y
  73         select HAVE_OPROFILE
  74         select HAVE_KPROBES
  75         select HAVE_KRETPROBES
  76         select HAVE_KVM if 64BIT
  77         select HAVE_ARCH_TRACEHOOK
  78
  79 source "init/Kconfig"
  80
  81 menu "Base setup"
  82
  83 comment "Processor type and features"
  84
  85 source "kernel/time/Kconfig"
  86
  87 config 64BIT
  88         bool "64 bit kernel"
  89         help
  90           Select this option if you have a 64 bit IBM zSeries machine
  91           and want to use the 64 bit addressing mode.
  92
  93 config 32BIT
  94         bool
  95         default y if !64BIT
  96
  97 config SMP
  98         bool "Symmetric multi-processing support"
  99         ---help---
 100           This enables support for systems with more than one CPU. If you have
 101           a system with only one CPU, like most personal computers, say N. If
 102           you have a system with more than one CPU, say Y.
 103
 104           If you say N here, the kernel will run on single and multiprocessor
 105           machines, but will use only one CPU of a multiprocessor machine. If
 106           you say Y here, the kernel will run on many, but not all,
 107           singleprocessor machines. On a singleprocessor machine, the kernel
 108           will run faster if you say N here.
 109
 110           See also the SMP-HOWTO available at
 111           <http://www.tldp.org/docs.html#howto>.
 112
 113           Even if you don't know what to do here, say Y.
 114
 115 config NR_CPUS
 116         int "Maximum number of CPUs (2-64)"
 117         range 2 64
 118         depends on SMP
 119         default "32" if !64BIT
 120         default "64" if 64BIT
 121         help
 122           This allows you to specify the maximum number of CPUs which this
 123           kernel will support.  The maximum supported value is 64 and the
 124           minimum value which makes sense is 2.
 125
 126           This is purely to save memory - each supported CPU adds
 127           approximately sixteen kilobytes to the kernel image.
 128
 129 config HOTPLUG_CPU
 130         bool "Support for hot-pluggable CPUs"
 131         depends on SMP
 132         select HOTPLUG
 133         default n
 134         help
 135           Say Y here to be able to turn CPUs off and on. CPUs
 136           can be controlled through /sys/devices/system/cpu/cpu#.
 137           Say N if you want to disable CPU hotplug.
 138
 139 config MATHEMU
 140         bool "IEEE FPU emulation"
 141         depends on MARCH_G5
 142         help
 143           This option is required for IEEE compliant floating point arithmetic
 144           on older S/390 machines. Say Y unless you know your machine doesn't
 145           need this.
 146
 147 config COMPAT
 148         bool "Kernel support for 31 bit emulation"
 149         depends on 64BIT
 150         select COMPAT_BINFMT_ELF
 151         help
 152           Select this option if you want to enable your system kernel to
 153           handle system-calls from ELF binaries for 31 bit ESA.  This option
 154           (and some other stuff like libraries and such) is needed for
 155           executing 31 bit applications.  It is safe to say "Y".
 156
 157 config SYSVIPC_COMPAT
 158         bool
 159         depends on COMPAT && SYSVIPC
 160         default y
 161
 162 config AUDIT_ARCH
 163         bool
 164         default y
 165
 166 config S390_SWITCH_AMODE
 167         bool "Switch kernel/user addressing modes"
 168         help
 169           This option allows to switch the addressing modes of kernel and user
 170           space. The kernel parameter switch_amode=on will enable this feature,
 171           default is disabled. Enabling this (via kernel parameter) on machines
 172           earlier than IBM System z9-109 EC/BC will reduce system performance.
 173
 174           Note that this option will also be selected by selecting the execute
 175           protection option below. Enabling the execute protection via the
 176           noexec kernel parameter will also switch the addressing modes,
 177           independent of the switch_amode kernel parameter.
 178
 179
 180 config S390_EXEC_PROTECT
 181         bool "Data execute protection"
 182         select S390_SWITCH_AMODE
 183         help
 184           This option allows to enable a buffer overflow protection for user
 185           space programs and it also selects the addressing mode option above.
 186           The kernel parameter noexec=on will enable this feature and also
 187           switch the addressing modes, default is disabled. Enabling this (via
 188           kernel parameter) on machines earlier than IBM System z9-109 EC/BC
 189           will reduce system performance.
 190
 191 comment "Code generation options"
 192
 193 choice
 194         prompt "Processor type"
 195         default MARCH_G5
 196
 197 config MARCH_G5
 198         bool "S/390 model G5 and G6"
 199         depends on !64BIT
 200         help
 201           Select this to build a 31 bit kernel that works
 202           on all S/390 and zSeries machines.
 203
 204 config MARCH_Z900
 205         bool "IBM eServer zSeries model z800 and z900"
 206         help
 207           Select this to optimize for zSeries machines. This
 208           will enable some optimizations that are not available
 209           on older 31 bit only CPUs.
 210
 211 config MARCH_Z990
 212         bool "IBM eServer zSeries model z890 and z990"
 213         help
 214           Select this enable optimizations for model z890/z990.
 215           This will be slightly faster but does not work on
 216           older machines such as the z900.
 217
 218 config MARCH_Z9_109
 219         bool "IBM System z9"
 220         help
 221           Select this to enable optimizations for IBM System z9-109, IBM
 222           System z9 Enterprise Class (z9 EC), and IBM System z9 Business
 223           Class (z9 BC). The kernel will be slightly faster but will not
 224           work on older machines such as the z990, z890, z900, and z800.
 225
 226 endchoice
 227
 228 config PACK_STACK
 229         bool "Pack kernel stack"
 230         help
 231           This option enables the compiler option -mkernel-backchain if it
 232           is available. If the option is available the compiler supports
 233           the new stack layout which dramatically reduces the minimum stack
 234           frame size. With an old compiler a non-leaf function needs a
 235           minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
 236           -mkernel-backchain the minimum size drops to 16 byte on 31 bit
 237           and 24 byte on 64 bit.
 238
 239           Say Y if you are unsure.
 240
 241 config SMALL_STACK
 242         bool "Use 4kb/8kb for kernel stack instead of 8kb/16kb"
 243         depends on PACK_STACK && !LOCKDEP
 244         help
 245           If you say Y here and the compiler supports the -mkernel-backchain
 246           option the kernel will use a smaller kernel stack size. For 31 bit
 247           the reduced size is 4kb instead of 8kb and for 64 bit it is 8kb
 248           instead of 16kb. This allows to run more thread on a system and
 249           reduces the pressure on the memory management for higher order
 250           page allocations.
 251
 252           Say N if you are unsure.
 253
 254
 255 config CHECK_STACK
 256         bool "Detect kernel stack overflow"
 257         help
 258           This option enables the compiler option -mstack-guard and
 259           -mstack-size if they are available. If the compiler supports them
 260           it will emit additional code to each function prolog to trigger
 261           an illegal operation if the kernel stack is about to overflow.
 262
 263           Say N if you are unsure.
 264
 265 config STACK_GUARD
 266         int "Size of the guard area (128-1024)"
 267         range 128 1024
 268         depends on CHECK_STACK
 269         default "256"
 270         help
 271           This allows you to specify the size of the guard area at the lower
 272           end of the kernel stack. If the kernel stack points into the guard
 273           area on function entry an illegal operation is triggered. The size
 274           needs to be a power of 2. Please keep in mind that the size of an
 275           interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
 276           The minimum size for the stack guard should be 256 for 31 bit and
 277           512 for 64 bit.
 278
 279 config WARN_STACK
 280         bool "Emit compiler warnings for function with broken stack usage"
 281         help
 282           This option enables the compiler options -mwarn-framesize and
 283           -mwarn-dynamicstack. If the compiler supports these options it
 284           will generate warnings for function which either use alloca or
 285           create a stack frame bigger then CONFIG_WARN_STACK_SIZE.
 286
 287           Say N if you are unsure.
 288
 289 config WARN_STACK_SIZE
 290         int "Maximum frame size considered safe (128-2048)"
 291         range 128 2048
 292         depends on WARN_STACK
 293         default "2048"
 294         help
 295           This allows you to specify the maximum frame size a function may
 296           have without the compiler complaining about it.
 297
 298 config ARCH_POPULATES_NODE_MAP
 299         def_bool y
 300
 301 comment "Kernel preemption"
 302
 303 source "kernel/Kconfig.preempt"
 304
 305 config ARCH_SPARSEMEM_ENABLE
 306         def_bool y
 307         select SPARSEMEM_VMEMMAP_ENABLE
 308         select SPARSEMEM_VMEMMAP
 309         select SPARSEMEM_STATIC if !64BIT
 310
 311 config ARCH_SPARSEMEM_DEFAULT
 312         def_bool y
 313
 314 config ARCH_SELECT_MEMORY_MODEL
 315        def_bool y
 316
 317 config ARCH_ENABLE_MEMORY_HOTPLUG
 318         def_bool y
 319         depends on SPARSEMEM
 320
 321 config ARCH_ENABLE_MEMORY_HOTREMOVE
 322         def_bool y
 323
 324 source "mm/Kconfig"
 325
 326 comment "I/O subsystem configuration"
 327
 328 config MACHCHK_WARNING
 329         bool "Process warning machine checks"
 330         help
 331           Select this option if you want the machine check handler on IBM S/390 or
 332           zSeries to process warning machine checks (e.g. on power failures).
 333           If unsure, say "Y".
 334
 335 config QDIO
 336         tristate "QDIO support"
 337         ---help---
 338           This driver provides the Queued Direct I/O base support for
 339           IBM System z.
 340
 341           To compile this driver as a module, choose M here: the
 342           module will be called qdio.
 343
 344           If unsure, say Y.
 345
 346 config QDIO_DEBUG
 347         bool "Extended debugging information"
 348         depends on QDIO
 349         help
 350           Say Y here to get extended debugging output in
 351             /sys/kernel/debug/s390dbf/qdio...
 352           Warning: this option reduces the performance of the QDIO module.
 353
 354           If unsure, say N.
 355
 356 config CHSC_SCH
 357         tristate "Support for CHSC subchannels"
 358         help
 359           This driver allows usage of CHSC subchannels. A CHSC subchannel
 360           is usually present on LPAR only.
 361           The driver creates a device /dev/chsc, which may be used to
 362           obtain I/O configuration information about the machine and
 363           to issue asynchronous chsc commands (DANGEROUS).
 364           You will usually only want to use this interface on a special
 365           LPAR designated for system management.
 366
 367           To compile this driver as a module, choose M here: the
 368           module will be called chsc_sch.
 369
 370           If unsure, say N.
 371
 372 comment "Misc"
 373
 374 config IPL
 375         bool "Builtin IPL record support"
 376         help
 377           If you want to use the produced kernel to IPL directly from a
 378           device, you have to merge a bootsector specific to the device
 379           into the first bytes of the kernel. You will have to select the
 380           IPL device.
 381
 382 choice
 383         prompt "IPL method generated into head.S"
 384         depends on IPL
 385         default IPL_TAPE
 386         help
 387           Select "tape" if you want to IPL the image from a Tape.
 388
 389           Select "vm_reader" if you are running under VM/ESA and want
 390           to IPL the image from the emulated card reader.
 391
 392 config IPL_TAPE
 393         bool "tape"
 394
 395 config IPL_VM
 396         bool "vm_reader"
 397
 398 endchoice
 399
 400 source "fs/Kconfig.binfmt"
 401
 402 config FORCE_MAX_ZONEORDER
 403         int
 404         default "9"
 405
 406 config PROCESS_DEBUG
 407         bool "Show crashed user process info"
 408         help
 409           Say Y to print all process fault locations to the console.  This is
 410           a debugging option; you probably do not want to set it unless you
 411           are an S390 port maintainer.
 412
 413 config PFAULT
 414         bool "Pseudo page fault support"
 415         help
 416           Select this option, if you want to use PFAULT pseudo page fault
 417           handling under VM. If running native or in LPAR, this option
 418           has no effect. If your VM does not support PFAULT, PAGEEX
 419           pseudo page fault handling will be used.
 420           Note that VM 4.2 supports PFAULT but has a bug in its
 421           implementation that causes some problems.
 422           Everybody who wants to run Linux under VM != VM4.2 should select
 423           this option.
 424
 425 config SHARED_KERNEL
 426         bool "VM shared kernel support"
 427         help
 428           Select this option, if you want to share the text segment of the
 429           Linux kernel between different VM guests. This reduces memory
 430           usage with lots of guests but greatly increases kernel size.
 431           Also if a kernel was IPL'ed from a shared segment the kexec system
 432           call will not work.
 433           You should only select this option if you know what you are
 434           doing and want to exploit this feature.
 435
 436 config CMM
 437         tristate "Cooperative memory management"
 438         help
 439           Select this option, if you want to enable the kernel interface
 440           to reduce the memory size of the system. This is accomplished
 441           by allocating pages of memory and put them "on hold". This only
 442           makes sense for a system running under VM where the unused pages
 443           will be reused by VM for other guest systems. The interface
 444           allows an external monitor to balance memory of many systems.
 445           Everybody who wants to run Linux under VM should select this
 446           option.
 447
 448 config CMM_PROC
 449         bool "/proc interface to cooperative memory management"
 450         depends on CMM
 451         help
 452           Select this option to enable the /proc interface to the
 453           cooperative memory management.
 454
 455 config CMM_IUCV
 456         bool "IUCV special message interface to cooperative memory management"
 457         depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
 458         help
 459           Select this option to enable the special message interface to
 460           the cooperative memory management.
 461
 462 config PAGE_STATES
 463         bool "Unused page notification"
 464         help
 465           This enables the notification of unused pages to the
 466           hypervisor. The ESSA instruction is used to do the states
 467           changes between a page that has content and the unused state.
 468
 469 config VIRT_TIMER
 470         bool "Virtual CPU timer support"
 471         help
 472           This provides a kernel interface for virtual CPU timers.
 473           Default is disabled.
 474
 475 config VIRT_CPU_ACCOUNTING
 476         bool "Base user process accounting on virtual cpu timer"
 477         depends on VIRT_TIMER
 478         help
 479           Select this option to use CPU timer deltas to do user
 480           process accounting.
 481
 482 config APPLDATA_BASE
 483         bool "Linux - VM Monitor Stream, base infrastructure"
 484         depends on PROC_FS && VIRT_TIMER=y
 485         help
 486           This provides a kernel interface for creating and updating z/VM APPLDATA
 487           monitor records. The monitor records are updated at certain time
 488           intervals, once the timer is started.
 489           Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
 490           i.e. enables or disables monitoring on the Linux side.
 491           A custom interval value (in seconds) can be written to
 492           /proc/appldata/interval.
 493
 494           Defaults are 60 seconds interval and timer off.
 495           The /proc entries can also be read from, showing the current settings.
 496
 497 config APPLDATA_MEM
 498         tristate "Monitor memory management statistics"
 499         depends on APPLDATA_BASE && VM_EVENT_COUNTERS
 500         help
 501           This provides memory management related data to the Linux - VM Monitor
 502           Stream, like paging/swapping rate, memory utilisation, etc.
 503           Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
 504           APPLDATA monitor record, i.e. enables or disables monitoring this record
 505           on the z/VM side.
 506
 507           Default is disabled.
 508           The /proc entry can also be read from, showing the current settings.
 509
 510           This can also be compiled as a module, which will be called
 511           appldata_mem.o.
 512
 513 config APPLDATA_OS
 514         tristate "Monitor OS statistics"
 515         depends on APPLDATA_BASE
 516         help
 517           This provides OS related data to the Linux - VM Monitor Stream, like
 518           CPU utilisation, etc.
 519           Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
 520           APPLDATA monitor record, i.e. enables or disables monitoring this record
 521           on the z/VM side.
 522
 523           Default is disabled.
 524           This can also be compiled as a module, which will be called
 525           appldata_os.o.
 526
 527 config APPLDATA_NET_SUM
 528         tristate "Monitor overall network statistics"
 529         depends on APPLDATA_BASE
 530         help
 531           This provides network related data to the Linux - VM Monitor Stream,
 532           currently there is only a total sum of network I/O statistics, no
 533           per-interface data.
 534           Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
 535           APPLDATA monitor record, i.e. enables or disables monitoring this record
 536           on the z/VM side.
 537
 538           Default is disabled.
 539           This can also be compiled as a module, which will be called
 540           appldata_net_sum.o.
 541
 542 source kernel/Kconfig.hz
 543
 544 config S390_HYPFS_FS
 545         bool "s390 hypervisor file system support"
 546         select SYS_HYPERVISOR
 547         default y
 548         help
 549           This is a virtual file system intended to provide accounting
 550           information in an s390 hypervisor environment.
 551
 552 config KEXEC
 553         bool "kexec system call"
 554         help
 555           kexec is a system call that implements the ability to shutdown your
 556           current kernel, and to start another kernel.  It is like a reboot
 557           but is independent of hardware/microcode support.
 558
 559 config ZFCPDUMP
 560         tristate "zfcpdump support"
 561         select SMP
 562         default n
 563         help
 564           Select this option if you want to build an zfcpdump enabled kernel.
 565           Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
 566
 567 config S390_GUEST
 568 bool "s390 guest support (EXPERIMENTAL)"
 569         depends on 64BIT && EXPERIMENTAL
 570         select VIRTIO
 571         select VIRTIO_RING
 572         select VIRTIO_CONSOLE
 573         help
 574           Select this option if you want to run the kernel under s390 linux
 575 endmenu
 576
 577 source "net/Kconfig"
 578
 579 config PCMCIA
 580         def_bool n
 581
 582 config CCW
 583         def_bool y
 584
 585 source "drivers/Kconfig"
 586
 587 source "fs/Kconfig"
 588
 589 source "arch/s390/Kconfig.debug"
 590
 591 source "security/Kconfig"
 592
 593 source "crypto/Kconfig"
 594
 595 source "lib/Kconfig"
 596
 597 source "arch/s390/kvm/Kconfig"